I have a JBL micro stage II that worked great in China/HK on my 4th generation iPod. I purchased an iPod Nano Red here in the US, the speaker (using adapter from HK to US power) caused my iPod to skip songs even after a few notes or a few bars. I returned the iPod and it still skipped at the Apple store so it did damage the iPod. When I put in the new iPod, it skipped again. So I stopped using it. I was hoping to change the cord but it seems to be more mechanical than that. An Amazon customer complained of the same skipping.